Technical Field
This invention relates generally to the field of semiconductors and, more particularly, to approaches for forming a contact to a source-drain region.
Related Art
During fabrication, semiconductor devices such as field effect transistors (FETs) often include a stage in which a contact is formed to a source-drain region of the semiconductor device. In most applications, it is understood that low-resistance, stable ohmic contacts are critical for the performance and reliability of the semiconductor device. Conversely, poorly prepared junctions to semiconductors can show rectifying behavior by causing depletion of the semiconductor device near the junction, reducing the performance of the device. Because of the importance of the contacts, care is usually taken to insure that the materials and processes that best achieve the desired results are used.
Process dimensions of semiconductor devices continue to shrink, with increasingly more features being included on a single chip. As a result of this miniaturization, materials and/or processes that were once standard may provide unpredictable results or may cease to work altogether.